C++ interface of the initial environment that is provided to an L4 task. More...

#include <env>

Collaboration diagram for L4Re::Env:

Public Types
typedef l4re_env_cap_entry_t	Cap_entry
	C++ type for an entry in the initial objects array.

Public Member Functions
L4::Cap< Parent >	parent () const noexcept
	Object-capability to the parent.
L4::Cap< Mem_alloc >	mem_alloc () const noexcept
	Object-capability to the memory allocator.
L4::Cap< L4::Factory >	user_factory () const noexcept
	Object-capability to the user-level object factory.
L4::Cap< Rm >	rm () const noexcept
	Object-capability to the region map.
L4::Cap< Log >	log () const noexcept
	Object-capability to the logging service.
L4::Cap< L4::Thread >	main_thread () const noexcept
	Object-capability of the first user thread.
L4::Cap< L4::Task >	task () const noexcept
	Object-capability of the user task.
L4::Cap< L4::Factory >	factory () const noexcept
	Object-capability to the factory object available to the task.
l4_cap_idx_t	first_free_cap () const noexcept
	First available capability selector.
l4_fpage_t	utcb_area () const noexcept
	UTCB area of the task.
l4_addr_t	first_free_utcb () const noexcept
	First free UTCB.
Cap_entry const *	initial_caps () const noexcept
	Get a pointer to the first entry in the initial objects array.
Cap_entry const *	get (char const *name, unsigned l) const noexcept
	Get the Cap_entry for the object named name.
template<typename T>
L4::Cap< T >	get_cap (char const *name, unsigned l) const noexcept
	Get the capability selector for the object named name.
template<typename T>
L4::Cap< T >	get_cap (char const *name) const noexcept
	Get the capability selector for the object named name.
void	parent (L4::Cap< Parent > const &c) noexcept
	Set parent object-capability.
void	mem_alloc (L4::Cap< Mem_alloc > const &c) noexcept
	Set memory allocator object-capability.
void	rm (L4::Cap< Rm > const &c) noexcept
	Set region map object-capability.
void	log (L4::Cap< Log > const &c) noexcept
	Set log object-capability.
void	main_thread (L4::Cap< L4::Thread > const &c) noexcept
	Set object-capability of first user thread.
void	factory (L4::Cap< L4::Factory > const &c) noexcept
	Set factory object-capability.
void	first_free_cap (l4_cap_idx_t c) noexcept
	Set first available capability selector.
void	utcb_area (l4_fpage_t utcbs) noexcept
	Set UTCB area of the task.
void	first_free_utcb (l4_addr_t u) noexcept
	Set first free UTCB.
L4::Cap< L4::Scheduler >	scheduler () const noexcept
	Get the scheduler capability for the task.
void	scheduler (L4::Cap< L4::Scheduler > const &c) noexcept
	Set the scheduler capability.
L4::Cap< Itas >	itas () const noexcept
	Object-capability to the ITAS services.
void	itas (L4::Cap< Itas > const &c) noexcept
	Set the ITAS capability.
L4::Cap< Dbg_events >	dbg_events () const noexcept
	Object-capability to a debugger events service.
void	dbg_events (L4::Cap< Dbg_events > const &dbg_events) noexcept
	Set the dbg_events capability.
void	initial_caps (Cap_entry *first) noexcept
	Set the pointer to the first Cap_entry in the initial objects array.

Static Public Member Functions
static Env const *	env () noexcept
	Returns the initial environment for the current task.

Detailed Description

C++ interface of the initial environment that is provided to an L4 task.

The initial environment is provided to each L4 task that is started by an L4Re conform loader, such as the Moe root task. The initial environment provides access to a set of initial capabilities and some additional information about the available resources, such as free UTCBs (see Virtual Registers ) and available entries in capability table (provided by the micro kernel).

Each of the initial capabilities is stored at a fixed index in the task's capability table and the L4 runtime environment provides convenience functions to retrieve the capabilities. See the table below for an comprehensive overview.

Name	Object Type	Convenience Function
parent	L4Re::Parent	L4Re::Env::parent()
user_factory	L4::Factory	L4Re::Env::user_factory()
log	L4Re::Log	L4Re::Env::log()
main_thread	L4::Thread	L4Re::Env::main_thread()
rm	L4Re::Rm	L4Re::Env::rm()
factory	L4::Factory	L4Re::Env::factory()
task	L4::Task	L4Re::Env::task()
scheduler	L4::Scheduler	L4Re::Env::scheduler()
itas	L4Re::Itas	L4Re::Env::itas()

Additional information found in the initial environment is:

First free entry in capability table
The UTCB area (as flexpage)
First free UTCB (address in the UTCB area)

Include File: #include <l4/re/env>

env
Environment interface.

For an explanation of the default task capabilites see l4_default_caps_t.

For the C interface refer to Initial Environment.

Definition at line 78 of file env.

Member Function Documentation

◆ dbg_events() [1/2]

L4::Cap< Dbg_events > L4Re::Env::dbg_events ( ) const

inlinenoexcept

Object-capability to a debugger events service.

Returns: Dbg_events object-capability

This capability can be invalid.

Definition at line 310 of file env.

Referenced by dbg_events().

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◆ dbg_events() [2/2]

void L4Re::Env::dbg_events ( L4::Cap< Dbg_events > const & dbg_events )

inlinenoexcept

Set the dbg_events capability.

Parameters

dbg_events is the capability to be set for the debug events service.

Note that the capability can be invalid.

Definition at line 320 of file env.

References dbg_events().

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◆ env()

Env const * L4Re::Env::env ( )

inlinestaticnoexcept

Returns the initial environment for the current task.

Returns: Pointer to the initial environment class.

A typical use of this function is L4Re::Env::env()-><member>()

Examples: examples/clntsrv/src/client.cc, examples/libs/l4re/c++/mem_alloc/ma+rm.cc, examples/libs/l4re/c++/shared_ds/ds_clnt.cc, examples/libs/l4re/c++/shared_ds/ds_srv.cc, examples/libs/l4re/streammap/client.cc, and examples/sys/migrate/thread_migrate.cc.

Definition at line 96 of file env.

Referenced by L4virtio::Svr::Dev_config::Dev_config(), L4virtio::Driver::Device::driver_connect(), L4vcpu::Vcpu::ext_alloc(), L4Re::Util::Event_t< Default_event_payload >::init(), L4Re::Util::Event_t< Default_event_payload >::init_poll(), L4Re::Util::kumem_alloc(), L4virtio::Driver::Block_device::setup_device(), and L4virtio::Driver::Virtio_net_device::setup_device().

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◆ factory() [1/2]

L4::Cap< L4::Factory > L4Re::Env::factory ( ) const

inlinenoexcept

Object-capability to the factory object available to the task.

Returns: Factory object-capability

Definition at line 144 of file env.

◆ factory() [2/2]

void L4Re::Env::factory ( L4::Cap< L4::Factory > const & c )

inlinenoexcept

Set factory object-capability.

Parameters

c	Factory object-capability

Definition at line 249 of file env.

◆ first_free_cap() [1/2]

l4_cap_idx_t L4Re::Env::first_free_cap ( ) const

inlinenoexcept

First available capability selector.

Returns: First capability selector.

First capability selector available for use for in the application.

Definition at line 152 of file env.

◆ first_free_cap() [2/2]

void L4Re::Env::first_free_cap ( l4_cap_idx_t c )

inlinenoexcept

Set first available capability selector.

Parameters

c	First capability selector available to the application.

Definition at line 255 of file env.

◆ first_free_utcb() [1/2]

l4_addr_t L4Re::Env::first_free_utcb ( ) const

inlinenoexcept

First free UTCB.

Returns: object-capability

First free UTCB within the UTCB area available for the application to use.

Definition at line 167 of file env.

◆ first_free_utcb() [2/2]

void L4Re::Env::first_free_utcb ( l4_addr_t u )

inlinenoexcept

Set first free UTCB.

Parameters

u	First UTCB available for the application to use.

Definition at line 267 of file env.

◆ get()

Cap_entry const * L4Re::Env::get	(	char const *	name,
		unsigned	l ) const

inlinenoexcept

Get the Cap_entry for the object named name.

Parameters

name	is the name of the object.
l	is the length of the name, thus name might not be zero terminated.

Returns: A pointer to the Cap_entry for the object named name, or NULL if no such object was found.

Definition at line 185 of file env.

References l4re_env_get_cap_l().

Referenced by get_cap().

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◆ get_cap() [1/2]

template<typename T>

L4::Cap< T > L4Re::Env::get_cap ( char const * name ) const

inlinenoexcept

Get the capability selector for the object named name.

Parameters

name	is the name of the object (zero terminated).

Returns: A capability selector for the object named name, or an invalid capability selector if no such object was found.

Definition at line 212 of file env.

References get_cap().

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◆ get_cap() [2/2]

template<typename T>

L4::Cap< T > L4Re::Env::get_cap	(	char const *	name,
		unsigned	l ) const

inlinenoexcept

Get the capability selector for the object named name.

Parameters

name	is the name of the object.
l	is the length of the name, thus name might not be zero terminated.

Returns: A capability selector for the object named name, or an invalid capability selector if no such object was found.

Examples: examples/clntsrv/src/client.cc, examples/libs/l4re/c++/shared_ds/ds_clnt.cc, and examples/libs/l4re/streammap/client.cc.

Definition at line 197 of file env.

References get(), and L4_ENOENT.

Referenced by get_cap().

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◆ initial_caps() [1/2]

Cap_entry const * L4Re::Env::initial_caps ( ) const

inlinenoexcept

Get a pointer to the first entry in the initial objects array.

Returns: A pointer to the first entry in the initial objects array.

Definition at line 174 of file env.

◆ initial_caps() [2/2]

void L4Re::Env::initial_caps ( Cap_entry * first )

inlinenoexcept

Set the pointer to the first Cap_entry in the initial objects array.

Parameters

first is the first element in the array.

Definition at line 327 of file env.

◆ itas() [1/2]

L4::Cap< Itas > L4Re::Env::itas ( ) const

inlinenoexcept

Object-capability to the ITAS services.

Returns: ITAS object-capability

Attention: this capability might be invalid, depending on the system configuration. Regular applications must not use it directly as it is an implementation detail of the L4Re libc that is subject to change without notice!

Definition at line 294 of file env.

◆ itas() [2/2]

void L4Re::Env::itas ( L4::Cap< Itas > const & c )

inlinenoexcept

Set the ITAS capability.

Parameters

c	is the capability to be set as ITAS.

Definition at line 301 of file env.

◆ log() [1/2]

L4::Cap< Log > L4Re::Env::log ( ) const

inlinenoexcept

Object-capability to the logging service.

Returns: Log object-capability

Definition at line 126 of file env.

◆ log() [2/2]

void L4Re::Env::log ( L4::Cap< Log > const & c )

inlinenoexcept

Set log object-capability.

Parameters

c	Log object-capability

Definition at line 237 of file env.

◆ main_thread() [1/2]

L4::Cap< L4::Thread > L4Re::Env::main_thread ( ) const

inlinenoexcept

Object-capability of the first user thread.

Returns: Object-capability of the first user thread.

Definition at line 132 of file env.

◆ main_thread() [2/2]

void L4Re::Env::main_thread ( L4::Cap< L4::Thread > const & c )

inlinenoexcept

Set object-capability of first user thread.

Parameters

c	First thread's object-capability

Definition at line 243 of file env.

◆ mem_alloc() [1/2]

L4::Cap< Mem_alloc > L4Re::Env::mem_alloc ( ) const

inlinenoexcept

Object-capability to the memory allocator.

Returns: Memory allocator object-capability

Examples: examples/libs/l4re/c++/shared_ds/ds_srv.cc.

Definition at line 109 of file env.

◆ mem_alloc() [2/2]

void L4Re::Env::mem_alloc ( L4::Cap< Mem_alloc > const & c )

inlinenoexcept

Set memory allocator object-capability.

Parameters

c	Memory allocator object-capability

Definition at line 225 of file env.

◆ parent() [1/2]

L4::Cap< Parent > L4Re::Env::parent ( ) const

inlinenoexcept

Object-capability to the parent.

Returns: Parent object-capability

Definition at line 103 of file env.

◆ parent() [2/2]

void L4Re::Env::parent ( L4::Cap< Parent > const & c )

inlinenoexcept

Set parent object-capability.

Parameters

c	Parent object-capability

Definition at line 219 of file env.

◆ rm() [1/2]

L4::Cap< Rm > L4Re::Env::rm ( ) const

inlinenoexcept

Object-capability to the region map.

Returns: Region map object-capability

Examples: examples/libs/l4re/c++/shared_ds/ds_clnt.cc, and examples/libs/l4re/c++/shared_ds/ds_srv.cc.

Definition at line 120 of file env.

◆ rm() [2/2]

void L4Re::Env::rm ( L4::Cap< Rm > const & c )

inlinenoexcept

Set region map object-capability.

Parameters

c	Region map object-capability

Definition at line 231 of file env.

◆ scheduler() [1/2]

L4::Cap< L4::Scheduler > L4Re::Env::scheduler ( ) const

inlinenoexcept

Get the scheduler capability for the task.

Returns: The capability selector for the default scheduler used for this task.

Definition at line 275 of file env.

◆ scheduler() [2/2]

void L4Re::Env::scheduler ( L4::Cap< L4::Scheduler > const & c )

inlinenoexcept

Set the scheduler capability.

Parameters

c	is the capability to be set as scheduler.

Definition at line 282 of file env.

◆ task()

L4::Cap< L4::Task > L4Re::Env::task ( ) const

inlinenoexcept

Object-capability of the user task.

Returns: Object-capability of the user task.

Definition at line 138 of file env.

◆ utcb_area() [1/2]

l4_fpage_t L4Re::Env::utcb_area ( ) const

inlinenoexcept

UTCB area of the task.

Returns: UTCB area

Definition at line 158 of file env.

◆ utcb_area() [2/2]

void L4Re::Env::utcb_area ( l4_fpage_t utcbs )

inlinenoexcept

Set UTCB area of the task.

Parameters

utcbs UTCB area

Definition at line 261 of file env.

The documentation for this class was generated from the following file:

l4/re/env

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ dbg_events() [1/2]

◆ dbg_events() [2/2]

◆ env()

◆ factory() [1/2]

◆ factory() [2/2]

◆ first_free_cap() [1/2]

◆ first_free_cap() [2/2]

◆ first_free_utcb() [1/2]

◆ first_free_utcb() [2/2]

◆ get()

◆ get_cap() [1/2]

◆ get_cap() [2/2]

◆ initial_caps() [1/2]

◆ initial_caps() [2/2]

◆ itas() [1/2]

◆ itas() [2/2]

◆ log() [1/2]

◆ log() [2/2]

◆ main_thread() [1/2]

◆ main_thread() [2/2]

◆ mem_alloc() [1/2]

◆ mem_alloc() [2/2]

◆ parent() [1/2]

◆ parent() [2/2]

◆ rm() [1/2]

◆ rm() [2/2]

◆ scheduler() [1/2]

◆ scheduler() [2/2]

◆ task()

◆ utcb_area() [1/2]

◆ utcb_area() [2/2]